Journal ArticleDOI
Flood Basalts and Hot-Spot Tracks: Plume Heads and Tails
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TLDR
Continental flood basalt eruptions have resulted in sudden and massive accumulations of basaltic lavas in excess of any contemporary volcanic processes, thought to result from deep mantle plumes.Abstract:
Continental flood basalt eruptions have resulted in sudden and massive accumulations of basaltic lavas in excess of any contemporary volcanic processes. The largest flood basalt events mark the earliest volcanic activity of many major hot spots, which are thought to result from deep mantle plumes. The relative volumes of melt and eruption rates of flood basalts and hot spots as well as their temporal and spatial relations can be explained by a model of mantle plume initiation: Flood basalts represent plume "heads" and hot spots represent continuing magmatism associated with the remaining plume conduit or "tail." Continental rifting is not required, although it commonly follows flood basalt volcanism, and flood basalt provinces may occur as a natural consequence of the initiation of hot-spot activity in ocean basins as well as on continents.read more
Citations
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Different Degrees of Partial Melting of the Enriched Mantle Source for Plio−Quaternary Basic Volcanism, Toprakkale (Osmaniye) Region, Southern Turkey
TL;DR: The Toprakkale (Osmaniye) region, located in the Yumurtalik fault zone in southern Turkey, contains Quaternary volcanic rocks, shown by their mineralogical and petrographical features to be alkali basaltic and basanitic.
Journal ArticleDOI
Does active mantle upwelling help drive plate motions
TL;DR: In this paper, the authors used a numerical mantle flow model to predict present-day plate motions driven by various combinations of upwelling and downwelling flow, and obtained a good fit to observed plate motions using flow driven only by downgoing mantle slabs, whose densities can be inferred either from tectonic history of subduction or from positive velocity anomalies extracted from mantle tomography.
Journal ArticleDOI
Mantle plumes and their effect on the Earth's surface: a review and synthesis
TL;DR: A starting mantle plume produces a distinctive signature on the surface of the Earth, consisting of a flood basalt and a chain of progressively younger volcanoes terminating at a hotspot that is currently volcanically active as discussed by the authors.
Carbon in the Convecting Mantle
Erik H. Hauri,Elizabeth Cottrell,Katherine A. Kelley,Jordan Tucker,K. Shimizu,Marion Le Voyer,J. P. Marske,Alberto E. Saal +7 more
Abstract: The flux of magmatic CO2 into the oceans and atmosphere contributes to the global surface carbon cycle, and changes in basaltic magma production and associated degassing have been proposed as one of several important forcing mechanisms that have influenced past global climate variations. Despite this degassing, the vast majority of Earth’s carbon is present not at the surface but in Earth’s convecting mantle. The convecting mantle is the part of the mantle that lies beneath tectonic plates, and its motions over geologic timescales are driven by the sinking of cold oceanic plates into the interior and hot active upwellings originating from great depth. The convecting upper mantle rises, melts, and erupts mid-ocean ridge basalt (MORB) due to seafloor spreading along the 56,000‐km length of the global mid-ocean ridge system. Active upwellings, driven by mantle buoyancy, produce intraplate and near-ridge hot spots (e.g. Hawaii, Iceland) that erupt ocean island basalt (OIB) with a smaller overall flux. Occasionally, however, active upwellings produce large igneous provinces (LIPs; e.g. Ontong–Java Plateau, Caribbean–Columbian Plateau, Manihiki Plateau, Kerguelen Plateau) characterized by enormous outputs of magma erupted over very short timescales. These flood basalt eruptions have often coincided in time with global climate crises and mass species extinctions. Ridges, hot spots, and LIPs represent the main volcanic expressions of the delivery of heat to Earth’s surface by the ongoing motions of the convecting mantle. Seafloor dredging and core recovery have produced tens of thousands of individual submarine glass and rock samples. Study of these samples has demonstrated that variations in the major and trace element chemistry of MORBs and OIBs are primarily the result of crystal fractionation following polybaric melting of mantle sources at different depths and variable temperatures. At the same time, isotopic differences between MORBs and OIBs show that the mantle sources of hot spots are much more diverse and heterogeneous than those of ridges, reflecting their derivation from distinct reservoirs within the convecting mantle consisting of numerous geochemically distinct components with varied origins and evolutions. Some of these reservoirs have retained anomalies in short-lived isotope systems that were active only in the first tens of millions of years of Earth’s
Journal ArticleDOI
Subsidence of the West Siberian Basin : effects of a mantle plume impact.
TL;DR: In this article, the authors compare subsidence patterns from one-dimensional conductive heat flow models to observed subsidence from backstripping studies of wells in the basin, and provide important constraints on the dynamics of mantle plume heads, and suggest a thermal control for the subsidence of the West Siberian Basin.
References
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Journal ArticleDOI
Magmatism at rift zones: The generation of volcanic continental margins and flood basalts
Robert S. White,Dan McKenzie +1 more
TL;DR: In this paper, the authors show that the production of magmatically active rifted margins and the effusion of flood basalts onto the adjacent continents can be explained by a simple model of rifting above a thermal anomaly in the underlying mantle.
Journal ArticleDOI
The Volume and Composition of Melt Generated by Extension of the Lithosphere
Dan McKenzie,Mike J. Bickle +1 more
Journal ArticleDOI
Geochim. cosmochim. acta
Book ChapterDOI
Plate Motions and Deep Mantle Convection
TL;DR: In this article, a scheme of deep mantle convection is proposed in which narrow plumes of deep material rise and then spread out radially in the asthenosphere, and thus their strikes show the direction the plates were moving as they were formed.
Journal ArticleDOI
Deccan flood basalts at the Cretaceous/Tertiary boundary?
Vincent Courtillot,Jean Besse,Didier Vandamme,Raymond Montigny,Jean-Jacques Jaeger,Henri Cappetta +5 more
TL;DR: In this paper, the Deccan continental flood basalts in India have been considered and it was suggested that volcanic activity may have lasted less than 1 Ma, thus possibly ranking as one of the largest volcanic catastrophes in the last 200 Ma.
Related Papers (5)
Magmatism at rift zones: The generation of volcanic continental margins and flood basalts
Robert S. White,Dan McKenzie +1 more